Automotive design is guided by a never-ending goal of improving the safety and comfort of passengers traveling within the vehicles. As the nature of existing vehicular travel precludes the ability to completely eliminate incidents of collision during operation, automotive designers pursue design improvements to minimize the impact of such collisions on the internal passengers. These design improvements often are located in a wide variety of components within the automobile. They may include a variety of features and functions from intrusion reduction to momentum absorbance.
One such category involves the use of energy seat impact response devices. These devices are utilized to protect passengers during collision. One example are safety mechanisms designed to move the head restraint forward in order to engage the passenger's head during rear-impact scenarios. By actively engaging the passenger's head, momentum from the passenger's head can be reduced and thereby further insure the comfort and safety of the passenger during collision. These safety mechanisms are commonly operated by rotating the head restraint assembly forward to engage the passenger. The nature of most head restraint shapes dictate that as they rotate the profile of their engagement surface with change. Additional designs considerations, therefore, must be imposed on the overall head restraint shape and design.
An improve approach would be to allow the head restraint assembly to be adjusted t coincide with an individual occupant's personal comfort and preferences. When the safety mechanism is deployed, it would be preferable that the head restraint be brought forward while retaining the configuration set for such personal comfort and preference. In this scenario the head restraint assembly would be properly configured to engage an occupants head even during forward-engaging motion. This could be accomplished by isolating the fore/aft motion necessary for engagement during impact from the adjustment features necessary for comfort. If combined with adjustment features that allowed the static distance from an occupant's head to the head restraint to be minimized, the pure linear forward engaging motion could be utilized to reduce engagement time during impact. This, in turn, could result in a further reduction in occupant realized stress which would be highly desirable.